macbook wont start up

I think you'll have to boot off your Install Disc.

Also, unplug any peripherals.

Not saying you have to reinstall...

"Try Disk Utility

1. Insert the Mac OS X Install disc that came with your computer, then restart the computer while holding the C key.
2. When your computer finishes starting up from the disc, choose Disk Utility from the Installer menu. (In Mac OS X 10.4 or later, you must select your language first.)
Important: Do not click Continue in the first screen of the Installer. If you do, you must restart from the disc again to access Disk Utility.
3. Click the First Aid tab.
4. Click the disclosure triangle to the left of the hard drive icon to display the names of your hard disk volumes and partitions.
5. Select your Mac OS X volume.
6. Click Repair. Disk Utility checks and repairs the disk."

http://docs.info.apple.com/article.html?artnum=106214

There indeed may be something wrong with it, but we're just other users here... have you tried Apple Hardware Test? (Holding the d key down while booting from the Install Disc).

Without it booting into Single User Mode... No.

If you had another IntelMac around & a Firewire cable you could use the FireWire target disk mode...

http://docs.info.apple.com/article.html?artnum=58583

If there was a Store handy that had DiskWarrior 4.1 from Alsoft...

http://www.alsoft.com/DiskWarrior/

Generally works better than DU.

Try fsck, or Safe Boot...

http://docs.info.apple.com/article.html?artnum=106214

Is there anyway to have this piece of crap deemed a lemon by Apple?

Since you just registered, It must be still under warranty, so bring it in to your local Apple shop!

Message was edited by: Dakota

Similar boat here. I booted up normally and, being a Friday night, checked Software update. The update for AirPort was posted. I had heard about it so I grabbed it and tried to restart. After failing several times I tried single user start up. I also received "read error 0x80000007. I've used an HP to google my way here. I did the OS Disc Install 1 and successfully ran Disc Utility- Repair Permissions & Disc. When I quit the disc and tried to reboot on the recognized hard disc volume it restarted, but back to the Install Disc. I restarted while holding down the space bar yet got no ejection of the disc. When I restarted again I got a file folder with a question mark for half a minute before the apple came back yet still did nothing. Every couple of minutes it restarts, gets to the apple and does nothing.

Help?

start a New Topic f you can for the most help, but try this...

Archive & Install
http://docs.info.apple.com/article.html?artnum=107120